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Discussion Starter #21
From an RT60 standpoint (really more for larger rooms but OK for reference), you'd want to be around 200ms in the midrange - maybe 250 in the lows and 160-170ms in the high end. You're really more interested in RT30 which is a bit more than 1/2 of those times but most people don't like it that dead.

Untreated, the low end is now probably closer to 1 second or a bit more.

Bryan
Thanks Bryan :T

I will measure on Saturday morning but I will probably need guidence if that is ok:please:

I will post the results on here.

Just one more thing, how do you cut rockwool into triangles?

Regards
Marty

Regards
 

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No problem.


Here is the cut pattern to turn 2'x4' sheets into 8 17x17x24" Triangles.



Use a sharp disposable razor knife to keep the blade sharp. 703 is more expensive but a lot easier to cut and work with.

Bryan
 

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Discussion Starter #23
No problem.


Here is the cut pattern to turn 2'x4' sheets into 8 17x17x24" Triangles.



Use a sharp disposable razor knife to keep the blade sharp. 703 is more expensive but a lot easier to cut and work with.

Bryan
703?
Razor Knife?

Sorry :huh:

Over here I know in our D.I.Y. store Wickes or B&Q they sell rockwool in rolls 50mm thick, not sure where to get sheets from?

I assume a razor knife would be the same as our retractable stanley knives?
 

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Pretty much the same thing. These would be disposable and have break off blades. Very thin blades, plastic housing, etc.

For sheets, look at an insulation supply house or a metal building insulation company.

Bryan
 

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Marty, I haven't used the newer version of REW yet, (Maybe this week...) but I believe you can view the waterfall graph for any measurements you have already taken and saved to disk. In the older version You could reopen them and select the waterfall tab to generate the graph. I thought I would mention that so you didn't think you had to set up all the gear and remeasure just to see the decay times for your current situation.

Matt
 

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Discussion Starter #31
Marty, I haven't used the newer version of REW yet, (Maybe this week...) but I believe you can view the waterfall graph for any measurements you have already taken and saved to disk. In the older version You could reopen them and select the waterfall tab to generate the graph. I thought I would mention that so you didn't think you had to set up all the gear and remeasure just to see the decay times for your current situation.

Matt
Thanks Matt but the thing that I need to look into is why my response with REW V5 seems quite a bit different from my older REW response, I am now concerned that my old results may not have been accurate so I feel like I need to get to grips with V5 and remeasure, then I can see if I can match the original results, then I can start learning how to use the waterfalls.

I shall have ago tomorrow :T

Regards
Marty
 

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Discussion Starter #32
Broadband bass absorption floor to ceiling in the 2 front corners. I'd also do some in the shorter left rear corner.

I would add at least 2-3 2" 2'x4' absorption panels on the left wall to bring better left to right symmetry by matching better with the curtains on the other side.

Ideally, the front wall would also be 100% dead to help with boundary interactions and to prevent reflections from the surround channels contaminating the front soundstage.

Bryan
Do I also need to put a panel on the bit of wall next to the front left speaker, at the same height or will the 2-3 panles along the wall at mid height be sufficient. Also once the front wall is absorbed can I push the speakers right into the corner or are they still better off staying about 2 feet away?

Regards
Marty
 

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Corner loading is almost never a good idea unless the speakers are specifically designed for it - which yours aren't. You would also like to try to make sure that the distance behind the speaker and the distance beside the speaker are not the same so the boundary interactions are different.

I'll have to go back and take a closer look on the short wall you're talking about.

Bryan
 

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Discussion Starter #34 (Edited)
Here are my measured results for sub+mains

number1.jpg

number1 waterfall.jpg

Not sure how best to show results in waterfall?

Would also like to know how good the sub response is, as it sounds great to me?
 
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